Fuel oxygen reduction unit

Abstract

An engine system is provided for an aircraft having an engine and an engine controller. The engine system includes: an electric machine configured to be in electrical communication with the engine controller for powering the engine controller; and a fuel oxygen reduction unit defining a liquid fuel flowpath and a stripping gas flowpath and configured to transfer an oxygen content of a fuel flow through the liquid fuel flowpath to a stripping gas flow through the stripping gas flowpath, the fuel oxygen reduction unit also in electrical communication with the electric machine such that the electric machine powers at least in part the fuel oxygen reduction unit.

What is claimed is: 
     
         1 . An engine system for an aircraft having an engine and an engine controller, the engine system comprising:
 an electric machine configured to be in electrical communication with the engine controller for powering the engine controller; and   a fuel oxygen reduction unit defining a liquid fuel flowpath and a stripping gas flowpath and configured to transfer an oxygen content of a fuel flow through the liquid fuel flowpath to a stripping gas flow through the stripping gas flowpath, the fuel oxygen reduction unit also in electrical communication with the electric machine such that the electric machine powers at least in part the fuel oxygen reduction unit.   
     
     
         2 . The engine system of  claim 1 , wherein the engine comprises an accessory gearbox, and wherein the electric machine is drivingly coupled to the accessory gearbox. 
     
     
         3 . The engine system of  claim 1 , wherein the fuel oxygen reduction unit comprises a gas pump in airflow communication with the stripping gas flowpath, and wherein the gas pump is powered at least in part by the electric machine. 
     
     
         4 . The engine system of  claim 1 , wherein the fuel oxygen reduction unit comprises a gas pump in airflow communication with the stripping gas flowpath, a contactor in fluid communication with the liquid fuel flowpath and the stripping gas flowpath for generating a fuel/gas mixture, and a separator for receiving the fuel/gas mixture from the contactor, wherein the gas pump, the separator, or both is powered at least in part by the electric machine. 
     
     
         5 . The engine system of  claim 1 , wherein the electric machine is a permanent magnet alternator, and wherein the engine controller is a full authority digital engine control engine controller. 
     
     
         6 . The engine system of  claim 1 , wherein the engine is a gas turbine engine. 
     
     
         7 . The engine system of  claim 1 , further comprising:
 a power electronics assembly positioned electrically between the electric machine and the fuel oxygen reduction unit.   
     
     
         8 . The engine system of  claim 7 , wherein the power electronics assembly includes an inverter, a rectifier, or both. 
     
     
         9 . The engine system of  claim 7 , wherein the power electronics assembly includes a rectifier located proximate the electric machine and an inverter located proximate the fuel oxygen reduction unit. 
     
     
         10 . The engine system of  claim 1 , wherein the electric machine is configured to provide substantially all of the electric power generated by the electric machine to the engine controller and the fuel oxygen reduction unit. 
     
     
         11 . The engine system of  claim 1 , wherein the electric machine is configured to provide substantially all of the electric power generated by the electric machine to the engine controller, the fuel oxygen reduction unit, and an electrical sink 
     
     
         12 . A method for operating an engine system for an aircraft, the method comprising:
 providing electrical power from an electric machine to an engine controller;   providing electrical power from the electric machine to a fuel oxygen reduction unit; and   reducing an oxygen content of a fuel flow with the fuel oxygen reduction unit using at least in part the electrical power received from the electric machine.   
     
     
         13 . The method of  claim 12 , wherein providing electrical power from the electric machine to the fuel oxygen reduction unit comprises providing electrical power from the electric machine to the fuel oxygen reduction unit concurrently with providing electrical power from the electric machine to the engine controller. 
     
     
         14 . The method of  claim 12 , further comprising:
 operating an engine of the aircraft in a first operating condition, wherein the engine controller is an engine controller for the engine; and   operating the engine of the aircraft in a second operating condition different than the first operating condition;   wherein providing electrical power from the electric machine to the engine controller comprises providing a substantially constant amount of electrical power from the electric machine to the engine controller when the engine is operated in the first and second operating conditions.   
     
     
         15 . The method of  claim 14 , wherein providing electrical power from the electric machine to the fuel oxygen reduction unit comprises providing a first amount of electrical power to the fuel oxygen reduction unit when the engine is operating in the first operating condition, and providing a second amount of electrical power to the fuel oxygen reduction unit when the engine is operating in the second operating condition, the first amount of electrical power being different than the second amount of electrical power. 
     
     
         16 . The method of  claim 12 , further comprising:
 driving the electric machine with an accessory gearbox of an engine of the aircraft.   
     
     
         17 . The method of  claim 12 , wherein providing electrical power from the electric machine to the fuel oxygen reduction unit comprises providing electrical power from the electric machine to an electric motor, the electric motor driving a gas boost pump of a fuel oxygen reduction unit. 
     
     
         18 . The method of  claim 12 , wherein the electric machine is a permanent magnet alternator, and wherein the engine controller is a full authority digital engine control engine controller. 
     
     
         19 . The method of  claim 12 , wherein providing electrical power from the electric machine to the fuel oxygen reduction unit comprises providing substantially all of an amount of electrical power generated by the electric machine to the fuel oxygen reduction unit and the engine controller. 
     
     
         20 . A method for operating an engine system comprising:
 reducing an oxygen content of a fuel flow to an engine of the engine system using a fuel oxygen reduction unit, wherein reducing the engine content of the fuel flow to the engine of the engine system using the fuel oxygen reduction unit comprises consuming a total amount of power with the fuel oxygen reduction unit in BTU per minute;   wherein the fuel flow defines a power in BTU per minute, and wherein a ratio of the total amount of power to the power within the fuel flow is between 0.0002:1 and 0.002:1.